Superheater



T. E. MURRAY April 7, 1931.

SUPERHPIA TER Filed May 29, 1924 I N I//i/VTOR Patented Apr. 7, 193,1 l'

UNITED STATES` PATENT OFFICE THOMAS E. MURRAY, OF BROOKLYN, NEW YORK; JOSEPH-BRADLEY MURRAY, THOMAS E. MURRAY, JR., AND JOHN F. MURRAY, EXECUTORS OF SAID THOMAS E. MURRAY,

DECEASED, ASSIGNORS TO METROPOLITAN ENGINEERING COMPANY, A CORPORA- irIoN or NEW vom:

applicatie ma ny 2a, um.` serial ne. 716,534. l

In certain prior a plications for exam le No. 678,443, I havl shown sind described f boilers made with a water screen or water wall in the furnace proper composed of tubes located against the inner face of the furnace wall and having lateral fins extending over l the spaces between the tubes by which the su erheaters utilizing the conducting efexposureto the .furnace heat.

iiciency of iins 'or fianges exposed to the radiant heat of the furnace and conducting such heat eiiicientlyk to the superheater tubes, which, however, are protected a ainst'direct d the improvements described, though applicable chieiy to superheaters, may be emplo ed in a varlety of apparatus in lwhich it 1s ,esired to apply the heat of a furnace to a liquid or a ilui passing through a tubular structure. l

Thevaccom anying drawings illustrate embodiments o the invention.

Fig. 1 is a longitudinal section of one style o f su rheater and Fi 2 a cross-sectionof a modi cation thereof; ig. 1 is a view of a modification Fiss style; l

Fig. 5 is a view from the right of Fig. 1 with the wall structure omitted. d

Referring to the embodiment of the invention illustrated the wall 1 of the furnace may be of any suitable refractory material on the be rectangular tubes as illustratedB in t views so as to reuire less thickness of the wall inner face where it'enclo'ses the tubes llite'reion of the wall are tubes 2 and 3 constitutmg the headers of asuperheater.- The may be ordias shownin i0P llor may for the embed ing of them. Superheater tubes 4 are arranged close to the inner face,

that is thefurnace sideo f the wall 1 and have their ends bent backward to enter the headers. The tubes 4 are provided with flanges.

which project' out into the furnaceand are exposed directly to the heat thereof? A suit 3 and 4 are similar views of another e other able form for the anges is shown by Fi 2. A pair of anges 5 is obtained by ben ing sheet metal'to a trough shape with a convex bottom 6 ittin the outer face of the tube 4 and welded t ereto. A good weldedjoint should be made so as toensure an area of contact equal at least to the combined thickness ofthe two flanges 5; the latter proiecting for part of their width into the furnace, 'the base of the anges and tube 4 being buried in and protected by the insulatin material of the wall 1 to an extent depen ingon the character of the furnace, its tem erature, and the rate of conduction of heat esired to the steam in the tubes 4.

TheJ structure of Figs.. 3 and 4 is similar in principle. The headers 2 and 3, however, are set with one face exposed toward the furnace. The tubes 7 run straight from the bottom of the header 2 into the top of the .header 3 and are thus embedded to some ex# 715,369, for heat conductin tubes filed May 23rd,"1924, Ihave described 1n detail the tubes and lins, and a variety of modifications thereof, such, for example, as the use of special metal for the fins to resist oxidation at high temperature, the use of 'diierent shapes, and the provision of interrupted fins to permit them to accommodate themselves better to the expansion caused by heat. All these features may be applied, as well as'others, to the anged tubes of the present ap lication.

' A suitable metal lfor t e fins or E ductin elements and one which is adapted at hig temperatures to have a higher resistance to oxidation than the *tubes is an iron allo containing chromium and nickel into the furnace eat conand the ke, althou h other` known higlly chamber.

A furnace chamber and exposed to the heat of 2. A boiler superheater comprising tubes embedded in a wall of a boiler furnace and heat conducting elements united to said tubes gud exposed to the heat of the furnace cham- 3. A boiler superheater comprising tubes embedded in "a wall of a boiler furnace and heat conductin elements united to said tubes and extending Veyond the inner face lof said boilerI furnace wall. f

4. A boiler superheater comprising tubes u embedded in a wall of a boiler furnace and heat conducting flanges secured to said tubes and extending beyond the inner face of said boiler furnace wall. i'

5. A boiler superheater comprising headers embedded in a furnace wall, tubes between v said headers also embedded in said wall and heat conducting elements secured to said tubes and extending beyond the inner face of said furnace wall.

6. A heater comprising tubes embedded in a furnace wall and heat conducting'elements united to said tubes and projecting into the 4 furnace chamber and exposed to the heat of the furnace chamber, said elements being formed at least in part of a metal of higher resistance to oxidation at high temperatures than the tubes.

p 7. A heater comprising tubes embedded in a furnace wall and heat conducting elements united to said tubes and projecting into the the furnace chamber, said elements being formed at least in ypart f an' alloyr of iron chromium and nickelv and at high temperatures havln 'a higher resistance to oxidation than said tu es'.

vIn witness whereofglv` have hereunto'signed i my name.

THOMAS E. iluminar.` 

